Vat-dyestuff.



I cific gravity diluted with little water-and heated to vat dyestuffs having the general formula: 10-

.hol, glacial acetic acid, benzene and chloroform with are diazotized with 20 parts by weight of hydrochloric UNITED STATES I PATENT- OFFICE.

KARL SOHIRMACHER AND-RIGHARD LEOPOLD, OF 'fiO(lHST-ON -THE-MAIN, GERMANY, ASSIGNORS TO FARBWERKE, VORM. MEISTER LUOIUQS & BRUNING, OF HOCHST-ON- THE-MAIN, GERMANY, A CORPORATION OF GERMANY.

' VAT-DYESTUFF.

Specification of Letters Patent.

Patented cat. 1, 1907.

I Application filed January 26,190T' Serial No. 864,167.

To all whom it may concern:

Be it known that we, KARL SCHIBMACHEB and RICH ARD LEOPOLD, both Ph. D., chemists, citizens of the Empire of Germany, and residing at Hochst-on-the- Main, Germany, have invented new and useful Improvements in Vat-Dyestuffsfof which the following is a specification. i The object of this invention is the improvement in wherein R' means ethyl and methyl.

The dyestufis may be obtained by oxidizing oxythionaphthene derivatives resulting from heating 4-alkylthiophenylthioglycollic-o-carboxylic acids with alkalies. The new dyestuffs are red powders, insoluble inwater. They are little soluble inthot alcoa yellow-red color, and are yielding withconcentrated sulfuric acid greenish-blue solutions. When heated. with hydrochloric acid to higher temperatures they split off alkyl chlorids. With alkaline hydrosulfite they yield yellow colored vats of the leucocompounds producing on cotton and wool beautiful shades similar to alizarin red.

The method to obtain the stance, as follows:

Example: 19.4 parts by weight of 4 acetamino-2- aminophenyl-l-carboxylic acid, obtained by oxidizing 2-nitro-4acetaminotoluene and subsequent reduction,.

new dyestuffs is, for inacid of'20 B. specific gravity and 6.9 parts by weight of nitrite and run intoa solution of 18 parts by weight of potassium xanthonate and 40 parts of sodium carbonate. On the evolution of nitrogen being complete 15 parts by weight of sodium chloracetate and 30 parts by weight of caustic soda-lye of 40 B. specific gravity are added and heated to about 100 C. for about 3 hours.

The solution obtained is filtered and'the 4-acetamino-- phenylthioglycollic-o-carboxylic acid is precipitatedwith a mineral acid. It is a yellowish "powder: T0

inophenylthioglycollic-o-carboxylic. acid are"dissolved with 40 parts by-weightoi soda-lye of 40. B. speboiling, till a test portion of the solution on addition 7 of hydrochloric acid no longer precipitates any unchanged acetyl derivative. The solution'is acidified,

sium-xanthogenate and 50 parts by weight of sodium carbonate. On the evolution of nitrogen being com-' plots the solution is filtered and the 4-xanthogenate derivative of phenylthioglycollic carboxylic acid of the iormula v (02115008906113:(SOHZOOOHWOOH is precipitated with a mineral acid and filtered. This I product is boiled on a reflux condenser for 6-8 hours with 35; parts by Weight of caustic soda-lye of 40 B. specific gravity'and a solution of 25 'parts by weight of sodium-ethylsulfate; the xanthogenate derivative is so transformed into. the 4-ethylthiophenylthioglycollic ortho-carboxylic acid. When cold it is filtered and the 4 ethylthiophenylthioglycollic-o-carboxylic acid is precipitated with a mineral acid. To transform it into the corresponding 4-ethyltbio-oxythionaphthene-carboxylic acid, 26 parts by weight of 4-ethylthiophenylthioglycollic-o-carboxylic acid are'introduced into a mixture of 150 parts by weight of caustic soda and 15 parts by weight of water, the whole being heated for some time to' l190- 0'. When cold it is dissolved in water and the 4-ethylthio-oxythionaphthenecarboxylic acid may be precipitated with a mineral acid as white powder. It may be re-crystallized from hot water, 111. p. about 188 C. Treated with nitrite and hydrochloric acidit yields, as also the 4-ethylthiooxythionaphthene, obtained fromthe acid by boiling with hydrochloric acid, a yellow nitroso compound.

onaphthene-carboxylic acid'aredissolved with 12 parts To obtain the dyestufi 21 parts of 4-ethylthio-oxythi- 'of soda-lye of 40 B, specific gravity in 1000 parts of I water to which is added at. gentle heat a 30 per cent .solution of 80 parts of pdtassiumderricyahid. The

,tion .by, ox idation eliminate the acetyl, 26 parts by weight of l-acetylam g 4 new my pr p rties is obtainedjby'= -o xidation of 4 methylthio oxytliionaphthne carboxdyestuff separates as red flakes and is isolated by filtration and washing with water. It may be purified by dissolving it in alkaline hydrosulfite and re-precipit'a with air. The properties are the aboveiinentioned.

obtained in analogous manner.

'Having now described our invention, what we claim As new products, the vat dyestuffs of which the compo sition corresponds to the formula:

10 wherein R" means ethyl and methyl, being red powders,

ting 01f when heated with hydrochloric acid alkyl chlorlds, dissolving in an alkaline hydrosulfli solution with a ycl- 15 low color to a vat, dyeing wool mm! cotton aliznrln-red tints.

In testimony, that wecluim the foregoing as our invention, we have signed our names in presence of two subscribing witnesses.

KARL SCHIRMACHER. RICHARD LEOPO LD.

Witnesses J EAN GRUND, CARL GRUND. 

